JPH0518148Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a print head mounting structure for mounting a print head in a printer.

[Conventional technology]

FIG. 3 is a schematic side view showing a print head mounting structure of a conventional printer, and FIG. 4 is an explanatory diagram of how the print head is mounted to a carriage in the same conventional example.

In the figure, reference numeral 1 denotes a carriage provided opposite to a platen 2, and a printing head 3 is detachably attached to the carriage 1 with screws 4.

The carriage 1 is guided by a guide shaft 5 and a guide beam 6 so that it can reciprocate in the printing line direction, and is driven by a motor and a power transmission mechanism (not shown).
Moves back and forth in the printing line direction.

7 is a head limiter made of an elastic member;
The head limiter 7 allows the distance between the wire tip 8a of the wire 8 of the print head 3 and the platen 2 to be
It is set within the specified size range. This is to prevent deterioration of print quality such as missing print dots and smudged characters, and to keep the reciprocating time of the wire 8 within a predetermined time.

When the motor (not shown) is driven with the above configuration, the carriage 1 is driven through the power transmission mechanism (not shown).
moves back and forth in the direction of the print line.

Therefore, the print head 3 mounted on the carriage 1 also reciprocates in the print line direction at the same time.

Every time the carriage 1 moves, for example, by one line, the wire 8 is driven to print dot characters on the paper 9. When the carriage 1 swings once, printing of one line is completed, so the paper 9 is fed by one line in preparation for printing the next line. In this way, the carriage 1 prints on the paper 9 while reciprocating.

When the wire 8 of the print head 3 wears out during repeated printing operations, the print head 3 is removed by removing the screw 4 as shown in FIG. 4, and a new print head 3 is installed using the screw 7.

[Problem that the invention attempts to solve]

However, in the conventional print head installation method with the above-mentioned configuration, if the centers of gravity of the head limiter and the print head are misaligned, the print head will tilt when it is placed against the head limiter and fixed with screws, making it difficult to completely contact the head limiter and fix it. If you press the printing head too hard against the head limiter, it may be difficult to
Since the head limiter is elastically deformed, it is not possible to set the distance between the wire tip and the platen to a predetermined dimension. As a result, there were problems such as deterioration of print quality such as missing dots and smudged characters, and the inability to print at high speed.

The present invention was developed in view of the above problems, and it is possible to install the print head so that it touches the head limiter without tilting, and to set the distance between the wire tip and the platen to a specified dimension. The purpose is to

The present invention further provides that when installing the print head,
To make it possible to set the distance between a wire tip and a platen to a predetermined dimension reproducibly by making the force for pressing a print head against a head limiter a constant force.

[Means for solving problems]

The present invention relates to a print head mounting structure for a printer in which a print head is fixed to a carriage that reciprocates in the print line direction opposite to a platen, with a protruding wire built-in part serving as a mounting surface. a head limiter that sets the tip of the print head at a constant distance from the platen; and a head limiter that opposes and applies a moment equal to the moment of weight of the print head from the mounting surface of the print head to the center of gravity, and on the other hand applies the urging force. The present invention is characterized in that a biasing member is provided for adjusting the pressing force of the print head against the head limiter to a constant value.

[Effect]

With the above configuration, the present invention uses a biasing member to bias a moment that is opposite to and equal to the moment of weight of the print head from the mounting surface to the center of gravity of the print head whose mounting surface and center of gravity are different from each other. The biasing force of the member can control the pressing force of the printing head against the head limiter to a constant value.

〔Example〕

Examples will be described below with reference to the drawings.

FIG. 1 is a side view showing an embodiment of the present invention, and FIG. 2 is an explanatory diagram of the force that acts when a print head is mounted in the same embodiment.

In the figure, reference numeral 10 denotes a carriage provided opposite to the platen 11, and the carriage 10 is attached to a guide shaft 1 so as to be able to reciprocate in the printing direction.
2 and a guide beam 13, and is reciprocated in the printing line direction by a motor and a power transmission mechanism (not shown).

Reference numeral 14 denotes a screw that fits into the fitting portion of the carriage 10, and the print head 15 is fixed onto the carriage 10 using the protruding wire built-in portion 16 as a mounting surface by the screw 14.

Reference numeral 17 denotes a head limiter made of an elastic member fixed to the carriage 10, and the head limiter 17 sets the distance between the wire tip 18a of the wire 18 of the print head 15 and the platen 11 within a predetermined range of dimensions. be.

Reference numeral 19 denotes a biasing member fixed to the carriage 10 together with the head limiter 17, and as shown in FIG.
The biasing force of the biasing member 19 is set so that the pressing force of the print head 15 against the head limiter 17 is a constant force F when it is brought into contact with the head limiter 17.

Also, the mounting is done so that a moment with the same magnitude and direction opposite to the moment l ₁ ×W, which is the product of the distance l ₁ between point A on the mounting surface and the center of gravity of the print head 15 and the weight W of the print head 15, acts. The point of action of the biasing member 19 acts on the print head 15 at a distance l ₂ from point A. That is, it is set so that l ₁ ×W=l ₂ F holds true.

The operation of this embodiment with the above configuration will be explained.

First, to mount the print head 15 on the carriage 10, the print head 15 is placed against the head limiter 17 and fixed to the carriage 10 with the screws 14. At this time, the biasing member 19 fixed to the carriage 10 together with the head limiter 17 biases the print head 15 in a state where the aforementioned l ₁ ×W = l ₂ F holds, and the pressing force of the print head 15 to the head limiter 17 is applied. is held constant.

After the print head 15 is mounted, the same printing operation as before on the paper 20 is repeated, and when the wire 18 of the print head 15 wears out, the screw 14 is removed and
Print head 15 is removed and a new print head 15 is installed in the same manner as described above.

[Effect of idea]

As explained in detail above, according to the present invention, a biasing member is provided which biases a moment that is opposite to and equal to the moment of the weight of the print head from the mounting surface to the center of gravity of the print head whose center of gravity is offset from the mounting surface. At the same time, the biasing member adjusts the pressing force of the print head against the head limiter to a constant level, so that when the print head is attached, the print head hits the head limiter with a constant biasing force, thereby reducing the pressure exerted by people or methods. Since there is no difference, the elastic deformation of the head limiter is constant, so the distance between the wire tip and the platen can be set accurately, and printing quality can be improved.

In addition, when installing the print head, the print head does not tilt, allowing it to come into perfect contact with the head limiter, allowing the distance between the wire tip and the platen to be set accurately, improving print quality. I can do it.

Furthermore, since the distance between the wire tip and the platen can be set accurately, the distance between the wire tip and the platen can be accurately set. Since this decreases, printing speed can be increased.

[Brief explanation of the drawing]

Fig. 1 is a side view showing an embodiment of the present invention, Fig. 2 is an explanatory diagram of the force that acts when mounting a print head in the same embodiment, and Fig. 3 is a conventional print head mounting structure of a printer. Schematic side view showing the fourth
The figure is an explanatory diagram of how the print head is attached to the conventional cartridge. 10...Carriage, 11...Platen, 14
... Screw, 15 ... Print head, 16 ... Wire built-in part, 17 ... Head limiter, 19 ... Biasing member.

Claims (1)

[Scope of Claim for Utility Model Registration] In a print head mounting structure for a printer in which the print head is fixed to a carriage that moves reciprocally in the printing line direction opposite to the platen, with the protruding wire built-in part serving as the mounting surface, a head limiter that sets the tip of the print head at a constant distance from the platen; and a head limiter that applies a moment that opposes and is equal to the moment of the weight of the print head from the mounting surface of the print head to the center of gravity. On the other hand, a print head mounting structure for a printer characterized in that a biasing member is provided which adjusts the pressing force of the print head against the head limiter to a constant level using the biasing force.